Best way to copy 31tb

[tucansam]

Guys, I have a ten-disk server and I am transitioning over to a second server.  I have 31TB of data to move.  

 

Can I power down the old server, pull a disk out, put it in the new server, mount it with Unassigned Devices, and move the data directly from the command line?  Seems like this would be the fastest way to move so much data at once.

 

Thanks.

[zonderling]

Why over complicate things?

I would just copy / paste over LAN and let it sit.

[tucansam]

I have tried this using several different methods, and the fastest I can get is 20MB/s.  So 30+TB at 20MB/s will take..... well..... it would be faster to pull disks and copy them individually at SATA II speeds.

[MrCrispy]

You should disable parity on the target server in any case. Then enable it back when all the data is there. 

If possible, you could also look at installing 10Gb cards in the 2 servers, they are not expensive (~$20) and this is the perfect use case.

 

20MBps seems really slow to me in any case, is that the read speed you get as well?

[tucansam]

If I disable parity, will I need to do a parity check once the data is moved?

 

10g cards is a good idea, I had no idea they were that cheap.

 

Read speeds are generally better, Windows copy over gig-e is 20MB/s, right now I am 'cp -R'ing from the command line and cannot measure speed.

[tucansam]

Using nload I am getting 250-300Mb/s on eth0 on the target server

[JorgeB]

Rsync with turbo write on (or no parity) should give you line speed with gigabit.

[tucansam]

rsync (with parity) is giving me 20-25MB/s

 

If I disable parity, should I run a parity check when the file copy is done?

[JorgeB]

You'll have to

[tucansam]

To disable parity, just unassign the parity disk?

[JorgeB]

Yes, also make sure you're not using the -z flag (compression) on the rsync command, or it will be muck slower for lan use.

[tucansam]

Yeah, thanks.  I was using it, figured out real quick it was slowing things down.  I'm averaging:

 

Device eth0 [192.168.0.5] (2/10):
================================================================================
Incoming:                               Outgoing:
Curr: 216.14 MBit/s                     Curr: 1.26 MBit/s
Avg: 445.31 MBit/s                      Avg: 2.50 MBit/s
Min: 952.00 Bit/s                       Min: 26.27 kBit/s
Max: 904.55 MBit/s                      Max: 13.86 MBit/s
Ttl: 3756.96 GByte                      Ttl: 1843.84 GByte
 

 

according to nload

 

Good enough for now.  I'm moving a few hundred gigs for now, and when its time for the huge batch move, I'll unassign the parity disk and see how much faster things go.

 

Thanks again.